The present invention relates to a watchcase, and more particularly to a watchcase having a shockproof structure for protecting a movement (including a module) provided in the case.
As one of the shockproof structures where the movement in the watchcase is protected from an externally applied shock, there is known a watchcase disclosed in Japanese Utility Model Application Laid Open 6-17110.
FIG. 47 is a sectional view showing a watchcase of the conventional art. The case has a shock absorber 3 made of such an elastic material as polyurethane rubber disposed between a metallic inner middle 1 and an outer middle 2 made of hard synthetic resin. The shock absorber 3 is inserted between the inner middle 1 and the outer middle 2 so as to cover an upper surface 1a of the inner middle 1 and the outer periphery of an annular projection 1b provided for holding a glass 4. The inner middle 1 and the outer middle 2 are attached to each other by a plurality of fixing screws 5. A metallic back 7 is fixed to the inner middle 1 by screws 8.
The shockproof structure is advantageous in that a shock applied to the watchcase is absorbed by elastic deformation of the shock absorber 3, thereby decreasing the shock transmitted to a movement 6.
FIG. 48 shows a section wherein a screw-lock crown is applied to the above-described prior art. The screw-lock crown comprises a support pipe 17 securely mounted in a hole 16a in the inner middle 1, a crown head 10 connected to the support pipe 17 by a screw thread 18, a stem connecting member 13 connected to a stem 11 of the watch and rotatably mounted in the support pipe 17, and a stopping ring 9 engaged with the stem connecting member 13.
When the crown head 10 is rotated so that the screw thread 18 is released from the support pipe 17, a coil spring 14 urges the head 10 to project outward. Hence, an engaging hole 15 polygonal in section and formed in an inner wall of the head engages a corresponding polygonal engaging portion 16 formed on the outer wall of the stem connecting member 13. When the head is rotated, the stem 11 is rotated by way of the stem connecting member 13, so that time can be set.
In order to protect the crown from shock, there is often provided a crown guard 19 in such a watch having a shockproof structure. The crown guard 19 comprises a pair of protecting wall projecting from the outer middle 2 so as to interpose the crown head 10 therebetween. The dimensions of the guard 19 with regard to both the height and the length thereof, are rendered larger than those of the crown head so as to prevent the shock from being exerted on the crown head 10. Hence it is possible to prevent such accidents as the stem 11 connected to the crown being bent or broken by the shock.
However, in the above-described shockproof structure, at the portion where the shock absorber is not provided, since an outer peripheral wall 1c of the inner middle 1 and an inner peripheral wall 2a of the outer middle 2 closely abuts against each other, the external shock exerted on the outer middle 2 may be directly transmitted to the inner middle 1. Moreover, the external shock exerted on the outer middle. 2 is also transmitted to the inner middle 1 through the fixing screws 5.
As a result, the shock is further applied to the movement 6 housed in the inner middle, so that the movement 6 may be broken.
More particularly, the underside of the inner middle 1 is covered neither by the shock absorber nor the outer middle. Thus, if the watch is dropped so that a shock is applied to the underside of the inner middle, the shock cannot be absorbed at all.
In addition, although the outer middle 2 covers the upper surface and the periphery of the inner middle, the underside of the inner middle is not covered. Hence, when the screws 8 become loose, the inner middle may fall out downwardly from the outer middle.
Furthermore, since the outer middle 2 of the above described shockproof structure is made of a synthetic resin, although hard, it does not have a sufficient strength, anti-scratch property and abrasion resistance. Accordingly, when an excessive degree of shock is applied to the watch, the outer middle of hard synthetic resin may be broken although the shock absorber interposed between the inner and outer middles can be elastically deformed. Moreover, if the watch is used for a long period of time, the outer middle may be injured or abraded.
In addition, if the fixing screws 5 become loose, the shock absorber 3 may be disengaged from the outer middle 2.
Meanwhile, in the case where the screw-lock crown is used as in FIG. 48, when a shock is exerted on the outer middle 2, the stem connecting member 13 and the stem 11 move into the movement 6, so that the stem bumps against the components such as gears in the movement. Thus the components of the movement may be displaced or broken.
On the other hand, since the crown guard 19 is larger than the crown head 10, the fingers of the watch wearer are hindered from touching the head 10. As a result, it is difficult to turn the crown head 10 with the fingers.
The first object of the present invention is to provide a shockproof structure for a watchcase where a shock is sufficiently absorbed.
The second object of the present invention is to provide a shockproof structure for a watchcase where an outer middle and an inner middle are securely fixed.
The third object of the present invention is to provide a shockproof structure for a watchcase having sufficient strength, anti-scratch property, and abrasion resistance.
The fourth object of the present invention is to provide a watchcase having a crown guard where the crown can be easily manipulated.
The fifth object of the present invention is to provide a watchcase where a shock absorber is not detached from a middle.
According to the present invention, there is provided a watchcase comprising a middle comprising a metallic inner middle in which a movement is housed, and a metallic outer middle covering at least a part of the inner middle, and an elastic shock absorber disposed between the inner middle and the outer middle.
According to another feature of the present invention, there is provided a watchcase comprising a middle comprising an inner middle in which a movement is housed, and an outer middle covering at least a part of the inner middle, and a securing member attached to the outer middle and inserted in the inner middle so that the inner and outer middles are attached to each other.
According to a further feature of the present invention, there is provided a watchcase comprising a middle comprising an inner middle in which a movement is housed, and an outer middle covering at least a part of the inner middle, an elastic shock absorber attached to one of the inner middle and the outer middle, a securing member having securing means on a part thereof and attached to one of the inner middle and the outer middle by the securing means so as to oppose the other middle interposing the shock absorber at a portion where the securing means is not provided.
According to a still further feature of the present invention, there is provided a watchcase comprising a crown, a stem connecting member provided on the crown, and connected to a stem of a movement housed in a middle, and a movement restricting member provided between the stem connecting member and the movement for restricting the movement of the stem connecting member and the stem toward the movement.
According to a still further feature of the present invention, there is provided a watchcase comprising a crown, and a guard pipe attached to a middle of the watchcase and in which guard pipe the crown is inserted, wherein an outer wall of a head of the crown is positioned at a position inner than an outer peripheral wall of the guard pipe.
According to a still further feature of the present invention, there is provided a watchcase having an elastic planar top shock absorber interposed between a bezel and a middle and a securing means for attaching the bezel and the middle to each other.
According to a still further feature of the present invention, there is provided a watchcase having an elastic ornamental ring shock absorber disposed between a shield holding member and an ornamental ring disposed above a dial.
According to a still further feature of the present invention, there is provided a watchcase having an elastic movement shock absorber provided between an ornamental ring disposed above a dial and a movement.
According to a still further feature of the present invention, there is provided a watchcase having an elastic bottom shock absorber disposed between an underside of a movement and a bottom of an inner wall of a middle.
According to a still further feature of the present invention, there is provided a watchcase comprising an inner middle in which a movement is housed and an outer middle covering at least a part of the inner middle, wherein the outer middle comprises an inner shell made of a hard material and an outer shell made of a soft material.
According to a still further feature of the present invention, there is provided a watchcase comprising an inner middle for housing a movement, and an outer middle for housing the inner middle, wherein the inner middle and the outer middle is attached to each other only by interposing a shock absorber therebetween.
According to a still further feature of the present invention, there is provided a watchcase comprising an inner middle for housing a movement, and an outer middle for housing the inner middle, including a shock absorber provided between the inner middle and the outer middle, wherein a space is formed between the inner middle and the outer middle except for a portion where the shock absorber is disposed.
According to a still further feature of the present invention, there is provided a watchcase having a pair of crown guards projecting adjacent a crown, wherein a notch is formed on each crown guard so as to expose an outer periphery of the crown.